Cats (domesticated form: Felis sylvestris libyca (bubastis))
are attested already in the 8th and 7th millennium BC in the Near East. In Egypt
remains of cats have been found in cemeteries of the Naqada Period (Brunton/Caton-Thompson
1928: 94). It is not possible to distinguish domesticated and wild forms
from skeletal remains. The domestication (better: taming) of the cat seems to
have started only in the New Kingdom (about 1550-1069 BC). Earlier depictions
(an uncertain example: UC 14323,
from Koptos) perhaps only show wild animals.
Apart from their usefulness in combating rats, mice and snakes, they were kept
as pets (especially well attested on many tomb paintings in the New Kingdom).

cats in religion
(click on the image for more information)

further reading:

Brussels
1989 (catalogue of an exhibition about cats in Ancient Egypt)